If the file to be inspected is not registerable, then the GUID & Name properties will not exist. Duh. Anyway, put a non-registerable file in, and it throws a com error. I thought that checking for @error would catch it. I either don't understand it implicitly or ... well, maybe I just don't understand it.

After I decrypted the help file on this library, and then reverse engineered it using a 128-bit offset alien to english text converter, I found this

tliErrCantLoadLibrary (vbObjectError + &H202)

The specified file could not be found, or the file doesn't contain a valid typelib.